1. Field of the Invention
This invention pertains to a drug delivery system. More specifically, the invention pertains to automatic delivery of a drug or drugs in single or multiple dosages. The invention includes an electronically programmable controller coupled to a low-profile module for attachment to a drug recipient and consisting of a multiple vesicle drug containment system and a plurality of different drug administration methods which are contained therein.
2. State of the Art
Administration of injectable drugs to a patient usually requires a trained and skilled professional to personally prepare the drug, prepare the patient, and administer the drug. If the drug requires injection, a needle must be inserted and removed. Typically, a clinical setting is required for but not limited to this type of drug administration because of the health risks when not using a sterilized environment. Furthermore, monitoring of the patient after drug delivery is often needed to evaluate drug therapy effectiveness or changing patient condition.
Automatically administering drugs without the need for a trained professional has so far met with limited success. To appreciate the dilemma fully, it is necessary to realize that it is not only the personal attention and skills required in administering drugs that make automation difficult to implement, but also the variety of situations in which drugs are administered. A further complication is that the great variety of drugs require different administration techniques.
For example, when a person requires regular insulin injections, that person is taught how to administer injections themselves. If the patient is young, other non-medical personnel are often taught how to administer drugs which severely hinders personal freedom of the drug administrator and the drug recipient. The situation is complicated in an emergency such as when a person goes into shock and is unable to personally inject the medication.
However, it is not only emergencies where automatic administration of drugs can be of benefit. For example, people who must work in confining conditions such as astronauts in space suits, pilots in combat aircraft, or soldiers in combat gear could also benefit from such a drug delivery system. In these situations, the cramped environment prohibits the manipulations necessary to administer a drug by self-administration by conventional means, thus creating a need for the present invention. Similarly, infantry soldiers fighting in the modern combat theater face deadly biological, chemical and nuclear threats that will almost certainly preclude advance drug therapy/prophylaxis of more than a few minutes in advance of critical need due to performance impairing side effects.
It should be apparent from the situations described that there are both military and civilian applications for an automatic drug delivery system capable of administering drugs which require a variety of delivery methods. The prior art solutions are limited in application and typically involve a single delivery method.
One example of a prolonged release drug delivery system that has recently become available is a transdermal patch that delivers a regulated dose of nicotine once it is attached to a smoker's skin. In a lipophilic form, the nicotine is absorbed through the skin, thereby alleviating the cravings for nicotine which is normally obtained through smoking. Unfortunately, very few drugs can be administered transdermally. Furthermore, even those that can be delivered transdermally are not necessarily conveniently administered when needed. There is a need for a drug delivery system that can handle a variety of delivery methods. There is also a need for the system to be automatic once a need for a drug is identified, thereby decreasing the possibility of human error in dosage, timing and delivery, especially under stressful conditions.
As the above situations illustrate, it would be an advantage over the prior art to provide an easily portable, automatic, electronically programmed and controlled multipathway drug delivery system that can be modified for the specific situation in which it will be used. It would be a further advantage if the system could be modified to include such things as programming to provide regular periodic injections, to thereby eliminate the chances of human error. The advantageous system would include different drugs and delivery modalities packaged in one device to provide alternative medical treatments if the drug therapy requirements change. It would also be an advantage over the prior art if a plurality of drugs requiring different delivery methods could all be administered from the same device. The device should be low-profile so that it can be strapped to a person ahead of time before entering an environment where medical attention by conventional means are difficult or impractical for such as reasons as urgency or space constraints. Therefore, ideally the system would be small, light weight, rugged, inexpensive and disposable.